1998 Ford Windstar -- horrible engine noise!

98 Ford Windstar -- terrible mystery engine noise. We replaced the lifters, rocker arms, and rods and changed the oil. The noise is just as bad if not worse. The first part of the audio is with the accelerator barely down, and the last part are sounds of the engine idling on its own. What should we try next? Click this link to hear the noise: http://www.youtube.com/watch?v=gDsbl2BD9Ls&feature=youtu.be

I have a 2000 ford windstar lx. it use to be a good van. but now it is haveing a problem. a bad one. it all started about a year ago. it was guzzling gas. i was told oxygen sensor. we replaced those. ...